1. Field of the Invention
The present invention relates to a print format selection device for cameras and lens-fitted photo film units, by which picture frames can be designated to be printed in different formats within a filmstrip, and by which the field of view of the viewfinder is changed in accordance with the designated print format.
2. Description of the Related Art
Compact reasonable cameras and lens-fitted photo film units, hereinafter referred to as film units, each preloaded with a photo film cartridge are getting more popular as a user-friendly snapshot camera. To add amusement in the snap-photography, a print system has been provided for making photo prints in different formats, including an ISO 135 standard size or 35 mm film size whose aspect ratio is about 1.5, an elongated panoramic size (P size) which is about double the ISO 135 size in length and thus has an aspect ratio of about 3.0, and a high-vision size (H size) whose aspect ratio is proximate to that of the high-vision TV screen, i.e. about 1.8. In general, the P size photo print is about 89 mm.times.127 mm, the H size photo print is about 89 mm.times.158 mm, and the ISO 135 size is about 89 mm.times.127 mm.
As one method for providing photo prints of different formats from a filmstrip, it is known to use a light shielding mask or blades to limit the exposure range on the filmstrip for each frame according to the designated print format, and make the photo prints from the exposure frames of correspondingly different aspect ratios. Regarding conventional ISO 135 or 35 mm film whose full size frame is 24 mm.times.36 mm, upper and lower portions of the full size frame exposure range are masked out for forming a P size exposure frame of 13 mm.times.36 mm, or a H size exposure frame of 20 mm.times.36 mm.
It is also known in the art to record every picture frame in the same size while recording data for designating a print format to each frame concurrently. According to this method, prints are made in the designated print formats from the same size picture frames by limiting the printing range of each frame corresponding to the aspect ratio of the designated print format. As the print format data recorded concurrently with each picture frame, it is known in the art to record a dot pattern on the photo film on one margin of the picture frame. JPA 8-160523 discloses a film unit utilizing ambient light for photographically recording the dot pattern on the photo film.
Recently, a new type photo film cartridge called IX 240 type or APS (Advanced Photo System) type has been brought to market. As disclosed for example in JPA 6-301157, the IX 240 photo film cartridge can contain a leader of a filmstrip therein and advance it to the outside by rotating its spool in an unwinding direction. The standard frame exposure range of the filmstrip contained in the IX 240 photo film cartridge is 16.7 mm.times.30.2 mm.
As the aspect ratio of the IX 240 standard frame is about 1.8, i.e. the H size, a H size photo print is made from the standard frame. In this case, a C size photo print that is equivalent to the ISO 135 standard photo print is made by limiting right and left portions of the standard frame exposure range or the printing range of the standard picture frame to 16.7 mm.times.23.4 mm. On the other hand, a P size photo print is made by limiting upper and lower portions of the standard frame exposure range or the printing range of the standard picture frame to 9.5 mm.times.30.2 mm.
Many of those cameras and film units which have the above described function to designate a different print format for each picture frame within a filmstrip concurrently with the exposure, also have a function to change the field of view in correspondence with the designated print format or printing range, so that the photographer can frame the photographic scene to be included in the individual photo print of the designated print format.
According to a method of changing over the field of view among three different sizes, a finder mask plate or view changing plate having two different windows is moved into an original field of view so as to limit the original view field by either of the two different windows. For example, in a 35 mm camera, the original view field shows a scene to be included in the ISO standard photo print, whereas the two different windows correspond to the P size print format and the H size print format respectively. The finder mask plate should be retracted from the field of view while the standard photo print is designated. Accordingly, it is necessary to provide the camera or the film unit with a relief space or room for allowing the finder mask plate to retract from the field of view.
Since the viewfinder is mostly disposed above the taking lens, the relief space can only be provided on horizontal sides of the viewfinder. Therefore, it is conventional to dispose two different windows side by side in an horizontally elongated finder mask plate, as shown for example in FIG. 28. The example of FIG. 28 relates to a camera for the IX 240 type photo film cartridge, so the original finder window 89 is the H size, and the finder mask plate 90 has the P size and the C size windows 92 and 93. In this case, a relief space 95 for retracting the P size window 92 from the H size finder window 89 while inserting the C size window 93 in the original field of view is necessary on one horizontal side of the finder window 89, and also a relief space 96 for retracting the finder mask plate 90 from the finder window 89 is necessary on the other horizontal side.
Where the H size finder window 89 has a length "A" in the horizontal direction, the space 95 and 96 should have at least the length "A" and a length "2.times.A" respectively in the horizontal direction. As a total, it is necessary for the finder mask plate 90 to provide at least a fourfold sliding space of the H size finder window. Consequently, the horizontally elongated conventional finder mask plate is disadvantageous for the film unit and the compact camera insofar as it limits compactness.